Remote control system for a locomotive

ABSTRACT

A remote control system for a locomotive. The remote control system includes a lead controller and follower controller connected to one another over a wireless communication link. The lead controller issues commands over the wireless communication link and those commands are implemented by the follower controller mounted on-board the locomotive. The lead controller is responsive to voice commands uttered by the operator.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 10/328,517 filed Dec. 23, 2002 now U.S. Pat. No. 6,799,098,which is a continuation-in-part of U.S. patent application Ser. No.10/222,560 filed Aug. 16, 2002 now U.S. Pat. No. 6,697,716, which is acontinuation of U.S. patent application Ser. No. 09/653,651 filed Sep.1, 2000 and issued Oct. 15, 2000 as U.S. Pat. No. 6,466,847. Thecontents of the above documents are incorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to locomotive remote control technology.

SUMMARY OF THE INVENTION

Under a first broad aspect, the invention provides a lead controller foruse with a remote control system for a locomotive. The lead controllercomprises an input for receiving a signal containing speech information.A processing unit receives the speech information and performs speechrecognition to generate speech recognition results. The processing unituses the speech recognition results to produce a command for executionby the locomotive. The lead controller also has a communication linkinterface and is operative for transmitting the command to be executedby the locomotive over a wireless communication link.

In a second broad aspect, the invention provides a remote control systemfor a locomotive that has a lead controller remote from the locomotiveand a follower controller designed to be mounted in the locomotive. Thelead controller can wirelessly transmit information to the followercontroller. The lead controller includes an input for receiving a signalderived from a spoken utterance and containing speech information. Theremote control system has a processing unit for performing speechrecognition on the speech information contained in the signal and usesthe speech recognition results to produce a command to be executed bythe locomotive.

In a third broad aspect, the invention provides a lead controller foruse with a remote control system for a locomotive. The lead controllercomprises an input interface for receiving a distance command. The leadcontroller also has a communication link interface for transmitting thedistance command to be executed by the locomotive over a wirelesscommunication link.

In a fourth broad aspect, the invention provides a remote control systemfor a locomotive that has a lead controller remote from the locomotiveand a follower controller to be mounted in the locomotive. The leadcontroller has an input interface for receiving from a human operator adistance command. The lead controller also has a communication linkinterface for transmitting the distance command over a wirelesscommunication link. The follower controller is responsive to thedistance command sent over the wireless communication link to cause thelocomotive to execute the distance command.

In a fifth broad aspect, the invention provides a lead controller foruse with a remote control system for a locomotive. The lead controllercomprises an input interface for receiving a target location command.The lead controller also has a communication link interface fortransmitting the target location command to be executed by thelocomotive over a wireless communication link.

In a sixth broad aspect, the invention provides a remote control systemfor a locomotive that has a lead controller remote from the locomotiveand a follower controller to be mounted in the locomotive. The leadcontroller has an input interface for receiving from a, human operator atarget location command. The lead controller also has a communicationlink interface for transmitting the target location command over awireless communication link. The follower controller is responsive tothe target location command sent over the wireless communication link tocause the locomotive to execute the target location command.

In a seventh broad aspect, the invention provides a lead controller foruse with a remote control system for a locomotive pulling a train. Thelead controller comprises an input interface for:

-   -   (a) receiving a command for execution by the train;    -   (b) a parameter of the train.

The lead controller has a communication link interface for transmittingthe parameter of the train and the command to be executed by the trainover a wireless communication link.

In an eight broad aspect, the invention provides a remote control systemfor a locomotive that has a lead controller remote from the locomotiveand a follower controller to be mounted in the locomotive. The leadcontroller includes an input interface for receiving:

-   -   (a) a command for execution by the train;    -   (b) a parameter of the train.

The remote control system has a communication interface for transmittingthe command and the parameter of the train over a wireless communicationlink. The follower controller is responsive to the command and to theparameter of the train sent over the wireless communication link tocause the train to execute the command by implementing actionsconditioned at least in part on the parameter of the train.

In a ninth broad aspect, the invention provides a lead controller foruse with a remote control system for a locomotive riding on a track. Thelead controller comprises an input interface for:

-   -   (c) receiving a command directing the locomotive to perform a        certain action;    -   (d) a parameter of the track.

The lead controller has a communication link interface for transmittingthe parameter of the track and the command for execution by thelocomotive over a wireless communication link.

In an tenth broad aspect, the invention provides a remote control systemfor a locomotive traveling on a track, that has a lead controller remotefrom the locomotive and a follower controller to be mounted in thelocomotive. The lead controller includes an input interface forreceiving:

-   -   (c) a command for execution by the locomotive;    -   (d) a parameter of the track.

The follower controller is responsive to the command and to theparameter of the track transmitted over the wireless communication linkto cause the locomotive to execute the command by implementing actionsconditioned at least in part on the basis of the parameter of the track.

BRIEF DESCRIPTION OF THE DRAWINGS

A detailed description of examples of implementation of the presentinvention is provided hereinbelow with reference to the followingdrawings., in which:

FIG. 1 is a block diagram of a remote control system for a locomotive;

FIG. 2 is a block diagram of the lead controller of the remote controlsystem for a locomotive depicted in FIG. 1;

FIG. 3 is a block diagram of a communication link interface of the leadcontroller shown in FIG. 2;

FIG. 4 is a flow-chart illustrating the operation of the lead controllershown in FIG. 2; and

FIG. 5 is a block diagram of a computing platform that can be used toimplement some of the components of the remote control system for alocomotive shown in FIG. 1; and

FIG. 6 is block diagram of a remote control system for a locomotiveaccording to a variant.

In the drawings, embodiments of the invention are illustrated by way ofexample. It is to be expressly understood that the description anddrawings are only for purposes of illustration and as an aid tounderstanding, and are not intended to be a definition of the limits ofthe invention.

DETAILED DESCRIPTION

A non-limiting example of implementation of the present invention isillustrated in FIG. 1 of the drawings. In particular, FIG. 1 illustratesa remote control system for a locomotive. The remote control systemincludes two main components, namely a lead controller 12 and a followercontroller 14 that are linked to one another by a wireless communicationlink 16.

In use, an operator dials in commands at the lead controller 12 andthose commands are relayed to the follower controller mounted on-boardthe locomotive. The follower controller will process the commands andissue local signals that-are applied to the locomotive such as toimplement the commands specified by the operator.

A detailed block diagram of the lead controller 12 is shown in FIG. 2.The lead controller includes an input interface (not shown) forreceiving commands from the operator as to desired actions to beexecuted by the locomotive or certain parameters about the train pulledby the locomotive or about the track on which the locomotive or train ismoving. The input interface refers broadly to the agency on the leadcontroller 12 on which commands and parameters can be input without anylimitation to the specific input devices used. The input devices maycomprise keys, switches, knobs or levers that must be displaced,depressed, or otherwise mechanically operated by the operator to dial incommands or parameters. Alternatively, the input interface may include apointing device, a touch sensitive screen or a voice input. In thespecific example described in this application, the input interface hasa voice input allowing the operator to enter commands or parameters viavoice. In a non-limiting example of implementation, the voice inputincludes a microphone.

In addition to the input interface, lead controller 12 includes aprocessing unit 15 and a communication link interface 32. The processingunit 15 has an input that receives a signal conveying speechinformation. In practice, if the voice input device on the inputinterface is a microphone, the input 17 could be the output from themicrophone. The signal at the input 17 is of analog nature. That signalis applied to an analog-to-digital converter 18 that digitizes thesignal according to a Pulse Code Modulation (PCM) technique or accordingto any other suitable method. The stream of PCM samples released fromthe analog-to-digital converter 18 are applied to a parameterizationunit 20 whose task is to extract from the audio signal containing thespeech information significant features on which further speechprocessing can be performed.

Examples of speech feature elements include feature vectors, spectralparameters, audio signal segments, band energies and cepstralparameters, among others.

It is not deemed necessary to describe in detail the structure andoperation of the parameterization unit 20 since such component is wellknown to those skilled in the art.

The feature elements extracted by the parameterization unit 20 arepassed to a speech recognition engine 22. Any suitable commerciallyavailable speech recognition engine can be used without departing fromthe spirit of the invention. The speech recognition engine 22 works inconjunction with a speech recognition dictionary 24 that contains a listof vocabulary items that the speech recognition engine 22 can recognize.In use, when the speech recognition engine 22 receives the featureelements generated by the parameterization unit 20, it generates atoutput 23 data that represents the vocabulary item best matching thespoken utterance characterized by the feature elements.

The vocabulary items held in the speech recognition dictionary 24reflect the commands that the lead controller 12 should be able torecognize.

For better recognition performance, the speech recognition engine 22 isspeaker dependent. In other words, the speech recognition engine 22should be trained from speech tokens from a specific speaker such thatthe speech recognition engine better adapts to the characteristics ofthe speaker. Alternatively, at speaker independent speech recognitionengine can be used without departing from the spirit of the invention.

The recognition results are released by the speech recognition engine 22on the output 23. In one specific example, the recognition results arethe vocabulary item found as being the best match to the spokenutterance, expressed in orthographic form. Other types ofrepresentations of the recognition results can be used without departingfrom the spirit of the invention.

The recognition results are input in a text to speech converter 25 thatsynthesizes an audio signal released on the output 19 to audibly play tothe user the recognition result. This mechanism is provided as a safetyfeature to allow the operator to abort a command in cases when therecognition results are incorrect. In a specific non-limiting example ofimplementation, the audio signal released from the text-to-speechconverter is in analog form. The analog signal is then passed to asuitable amplifier (not shown in the drawings) and a suitable speaker(not shown in the drawings) such as to audibly play the synthetic speechto the operator.

Any suitable text-to-speech converter could be used without departingfrom the spirit of the invention. In light of the fact thattext-to-speech converters are generally known in the art it is notdeemed necessary to describe them here in detail.

Instead of communicating audibly to the operator the recognition resultsfor verification purposes, the lead controller 12 can visuallycommunicate those results to the operator. For example, the leadcontroller 12 can be provided with a display on which the recognitionresults are shown.

The output 23 is also applied to a command verification unit 28. Thecommand verification unit gates the recognition results. If aconfirmation has been received from the operator within a specified timeperiod that the recognition result is accurate, the command verificationunit 28 will release the recognition result for further processing. Ifno positive input has been received from the operator within thespecified time period or a negative input has been received from theoperator, the command verification unit 28 deletes or otherwise negatesthe recognition results applied at its input.

In one specific example, the command verification unit 28 will releasethe recognition results only if the operator has uttered the word “yes”within a certain time frame after reception of the recognition results,say 5 seconds. After the recognition results are input in the commandverification unit 28, a timer starts. At the same time, the operatorreceives from the text-t-speech converter 26 synthesized speechconveying what are the recognition results. If the operator accepts theresults, he or she utters “yes”. The new spoken utterance is processedas described previously, and assuming a correct recognition theorthographic representation of the word “yes” appears at the output 23and it is supplied to the command verification unit 28. If the word“yes” is received before the expiration of the 5 seconds interval, theprior recognition results (conveying the original command) are releasedby the command verification unit 28. If nothing is received by thecommand verification unit 28 before the timer stops, then the priorrecognition results buffered in the command verification unit 28 aredeleted. The same operation is performed if any other word than “yes” isreceived by the command verification unit 28.

In the example of implementation shown in FIG. 2, the architecture ofthe system is such that the operator will also hear the recognitionresults from the confirmation utterance, namely the word “yes” (assumingcorrect recognition). In some applications, this might be desirable. Ifthis feature is not desirable, the system shown in FIG. 2 can bemodified such that a control signal is issued from the commandverification unit 28 while the timer is counting. The control signal isapplied to the text-to-speech converter 26 such as to prevent theconverter from operating. After the timer stops, the control signal isno longer generated and the text-to-speech converter 26 is re-activated.

In a possible variant, a confirmation other than a vocal confirmationcan be used. For instance, the lead controller 12 can be provided with abutton that that operator needs to depress in order to confirm therecognition results. This possibility can be implemented by modifyingthe command verification unit 28 to release the recognition results whena logic signal derived from the manual actuation of the button isreceived before the timer stops. This variant is particularly wellsuited to applications in which the recognition results are communicatedto the operator visually instead of audibly.

In another possible variant, the command verification unit 28 willinclude a speaker verification module allowing to verify that theoperator entering the voice command is an authorized user. Prior tousing the system, each authorized user will be asked to provide arespective access voiceprint associated to a user identification number.A voiceprint is a mathematical representation the acoustic properties ofa spoken utterance. The access voiceprint will be used to grant accessto the control system by performing a similarity measurement between theaccess voiceprint and an input utterance provided by the operator. Forincreased security, in addition to the identification number and accessvoiceprint, a speaker verification operation will be performed for eachcommand received from an operator. In this case, command voiceprints foreach allowable command will have to be provided by each authorized userprior to using the control system. These command voiceprints are storedin records in a computer readable medium and are associated torespective authorized user via their identification number. Once anoperator has been granted access to the control system by his accessvoiceprint, the corresponding record containing the command voiceprintsis extracted and used for subsequent speaker verification operations.Consequently, each spoken utterance indicative of a command received bythe control system is verified against the corresponding commandvoiceprint in the record associated to the given user. Speakerverification units are well-known and will not be further describedhere. If the operator cannot be verified as an authorized user, thesystem will issue a message indicating that control access is beingdenied.

When the recognition results are released from the command verificationunit 28, they are passed to a command translator. The purpose of thecommand translator is to encode the command in a format suitable forprocessing by the control unit 30 to be described later. Generallystated, the command released by the command validation unit is inorthographic form which is not the best form suited for analysis such asbasic sanity checks and other similar operations to be performed by thecontrol unit 30.

In a prior art lead controller, when the operator manually acts on thecontrols, the commands are encoded and supplied to a control unit. Inthe present example of implementation, the command translator willconvert the command that is orthographic representation to a formatnormally obtained from typical manually operated controls. This featureallows using a control unit 30 of known design since the control unit 30will receive commands in a format that it can already interpret.

The command translator 29 can be designed around a database that mapsthe orthographic representation of a command to its encoded form. Thesize of the database will depend upon the number of possible commandsthe lead controller 12 is designed to vocally accept.

The control unit 30 receives the encoded command and processes it. Onetype of processing is to perform a high-level validation or sanitycheck. For example, when the locomotive is travelling forward and acommand is received that specifies a reverse movement, that command isrejected. In general, the control unit 30 is of known construction andit does not need to be described in detail here. For more information,the reader is directed to the U.S. Pat. Nos. 5,511,749 and 5,685,507that provide more information on this particular point. The contents ofthese patents in incorporated herein by reference.

The output generated by the control unit 30 is passed to thecommunication link interface 32 such that it can be transmitted to thefollower controller 14 over the wireless communication link 16. Anexample of implementation of the communication link interface is shownin FIG. 3. The communication link interface includes a receiver unit 34and a transmitter unit 36. Signals issued from the control unit 30 arepassed to the transmitter unit 36 for modulation and any other suitableprocessing such as they can be transported over the wirelesscommunication link 16. Similarly, signals in the wireless communicationlink 16 directed at the lead controller 12 are passed to the receiverunit 34 for demodulation and they are then passed to the component ofthe lead control 12 designed to process them.

FIG. 4 is a flowchart that summarizes the operation of the leadcontroller 12. At the block 38, the process starts. At step 40, thevocal command uttered by the operator is received at the input 17. Atstep 42, the spoken utterance is recognized. At step 44, syntheticspeech is created and played to the operator to communicate to him therecognition results. At step 46, the recognition results are validated.At step 48, the validated recognition results are passed to the commandtranslator 29 for encoding and then to the control unit 30. At step 50;the command is sent to the follower controller 14 over the wirelesscommunication link 16.

The processing unit 15 can in large part be implemented in softwareexecuted on a suitable computing platform of the type illustrated inFIG. 5. Such computing platform includes a Central Processing Unit (CPU)60 connected to a memory 62 over a data bus 64. An Input/Outputinterface 66 is connected to the data bus 64 and allows the computingplatform to exchange signals/data with the external world. The memory 62is used for holding program instructions of program elements thatimplement the functionality of components of the processing unit 15.Also, the memory 62 is used to hold data on which the program elementsoperate.

The structure and operation of the follower controller 14 is notdescribed in detail in this specification. For more information thereader is directed to the U.S. Pat. Nos. 5,511,749 and 5,685,507.

FIG. 6 illustrates a variant of the remote control system for locomotive100. The remote control system 100 has a lead controller 102 that isgenerally similar to the lead controller 12 described earlier and afollower controller 104 that communicates with the lead controller 102via a communication link 106. The follower controller 104 causes thelocomotive to execute a number of functions, including traveling on thetrack a predetermined distance. The operator can input on the inputinterface of the lead controller 102 a distance command specifying thedistance to travel. Such distance command can be input as a distancevalue, such as 100 meters for example, or as a parameter that can beresolved by the remote control system 10 to a distance value.Accordingly, for the purpose of this specification, the expression“distance command” or command directing the locomotive to travel apredetermined distance” should be interpreted to cover commands thatspecify explicitly a distance to be travelled or a command that can beresolved into a distance to be travelled. An example of such a commandis a command directing the locomotive to move a predetermined number ofcar lengths. Since the length of a car is known, the remote controlsystem 100 can compute the total distance the locomotive is to travel bymultiplying the average length of a car by the number of cars specifiedby the operator.

The follower controller 104 uses a distance input in order to determinethe actual distance travelled by the locomotive such that when thedistance to travel has been reached, the movement can be stopped. Thereare a wide variety of ways to obtain the distance input, withoutdeparting from the spirit of the invention. For example:

-   -   (a) The distance input can be obtained internally by processing        the output of the velocity sensor mounted on the locomotive that        is used to measure the speed of the locomotive. The distance        travelled can be determined by integrating the velocity over the        time the locomotive is moving.    -   (b) If the velocity sensor uses a pulse generator, where each        pulse corresponds to a certain distance travelled, counting the        pulses represents a way to measure distance. Objectively,        methods (a) and (b) may introduce errors when the velocity        sensor is mounted on a traction wheel of the locomotive and that        wheel is subjected to slip.    -   (c) The distance input can be obtained externally, as shown by        the arrow 108, via transponder detection. The locomotive is        provided with an antenna that senses transponders placed at        predetermined locations along the track. Based on the identity        of a given transponder and knowing the location of each        transponder, the remote control system can derive the distance        traveled by the locomotive between two transponders.    -   (d) Another way to obtain the distance input externally is via a        Global Position System (GPS) that can provide travelled distance        information. For higher accuracy a differential GPS system can        be used.

In use, when the remote control system receives a distance command, thelocomotive either alone or when pulling a train will start moving whilemonitoring the distance travelled. When the locomotive approaches theend of the track span that corresponds to the distance to be travelled,the locomotive slows down by reduction of power and/or application ofbrakes such as to stop without exceeding the distance specified by theoperator.

In another possible variant, that is also described in conjunction withFIG. 6, the remote control system 100 is designed to receive a targetlocation command, which is a command identifying a location on the trackwhere the locomotive is to stop. In this embodiment, the remote controlsystem 100 tracks the current location of the locomotive and compares itto the target location. When the locomotive is at or near the targetlocation the remote control system 100 causes the locomotive to stop bypower reduction and/or application of brakes. The command supplied bythe operator provides the information about the target location. Forexample, a target location command can specify the identity of atransponder and the locomotive will stop when this transponder isreached. Alternatively, the target location command can specify alocation by expressing coordinates explicitly or implicitly. Forinstance, the operator may specify the name of a location that can beresolved to a set of coordinates by the remote control system.Alternatively, the operator may be provided on the input interface witha touch sensitive screen showing a map of the yard where the locomotiverides. The operator may touch or otherwise specify a location on thedisplayed map. Underlying logic in the lead controller 102 can issuebased on this input the coordinates, expressed in any suitable format,of the location specified by the operator.

Once the target location is known, the remote control system 100 candetermine when to stop the locomotive by tracking the current positionof the locomotive. The current position can be generated from a GPSunit, as depicted by the arrow 108, or by reading a transponder alongthe track.

In yet another possible variant the remote control system can receive,in addition to commands directing the locomotive to perform a certainfunction, parameters that can change the way the command is beingimplemented. For example, the operator may specify parameters about thetrain being pulled by the locomotive or parameters about the track onwhich the locomotive is riding. An example of a parameter of the trainis the approximate weight of the train or the number of cars in thetrain. This information can be used by the follower controller to adaptthe control logic that is used to regulate the train movement. Forinstance, in the case of a heavier train, more power can be applied whenthe operator desired to bring the train to certain speed, than in thecase of a lighter train. In a braking scenario, when the operatordesires to bring the train to a stop at a certain location, the controllogic will apply the brakes earlier than in the case of a lighter train,to avoid the train overshooting the target location. Accordingly, thelocomotive is caused to execute commands by implementing actions thatare conditioned on the parameter specified by the operator.

The control logic in the follower controller can usually be expressed asa set of transfer functions, each function associated to a certainoperation, such as acceleration, coasting, braking, etc. Each transferfunction has a number of control parameters. The parameters of the traininput by the operator used to modify the control parameters of therelevant transfer function. Which control parameters of the transferfunction, and the extent to which they can be modified, is a matter ofdesign choice that can vary significantly from one application to theother.

Another parameter that can be specified by the operator and that can beused to tailor the control logic of the follower controller generally asdescribed earlier, relates to track conditions. For example, theoperator can specify the grade (incline) of the track which informationcan be used modify the control logic to apply more power when the trainis going up the track and less power when the train is moving down, dueto the gravity effect. Braking can be tailored in a similar manner.Another possible track parameter, among others, is how slippery thetrack is.

Parameters about the train and track conditions, distance and targetlocation commands can be entered via voice. The speech recognitionfunctionality of the remote control system processes the speech input asrequired previously to output the relevant command or parameter, whichis then processed for implementation. The speech recognition dictionaryof the system contains vocabulary items that correspond to the distanceand target location commands, train, track or other parameters that thesystem should be able to recognize, such that when the operator uttersone or more of those commands or parameters the speech recognitionsystem will be able find proper matches.

It should be expressly noted that parameters about the train and trackconditions, and distance and target location commands could also bespecified by the operator by using input devices other than a speechsensing input.

Although various embodiments have been illustrated, this was for thepurpose of describing, but not limiting, the invention. Variousmodifications will become apparent to those skilled in the art and arewithin the scope of this invention, which is defined more particularlyby the attached claims.

1. A lead controller for a locomotive, comprising: a) an input forreceiving a signal containing speech information; b) a processing unitfor receiving the speech information and performing speech recognitionto generate speech recognition results and using the speech recognitionresults to produce a command for execution by the locomotive; c) acommunication link interface operative to maintain a wirelesscommunication link with a follower controller in a locomotive fortransmitting the command to be executed by the locomotive over thewireless a communication link.
 2. A lead controller as defined in claim1, including a microphone connected to said input.
 3. A lead controlleras defined in claim 1, wherein the signal containing speech informationis derived from a spoken utterance, said processing unit has a speechrecognition engine.
 4. A lead controller as defined in claim 3, whereinsaid processing unit includes a speech recognition dictionary includinga plurality of vocabulary items, said speech recognition engine beingoperative to identify amongst the plurality of vocabulary items at leastone vocabulary item that is a match to the spoken utterance.
 5. A leadcontroller as defined in claim 3, wherein said processing unit isoperative to communicate to a human operator information allowing theoperator to ascertain if the processing unit has correctly recognizedthe speech information.
 6. A lead controller as defined in claim 5,wherein the information allows the human operator to ascertain thespeech recognition results generated by said processing unit.
 7. A leadcontroller as defined in claim 6, wherein the information allows thehuman operator to ascertain the at least one vocabulary item identifiedby said speech recognition engine as being a match to the spokenutterance.
 8. A lead controller as defined in claim 6, wherein saidprocessing unit communicates the information to the human operatoraudibly.
 9. A lead controller as defined in claim 8, wherein saidprocessing unit communicates the information to the human operatorvisually.
 10. A lead controller as defined in claim 8, wherein theinformation is conveyed to the human operator by using synthetic speech.11. A lead controller as defined in claim 5, wherein said processingunit is responsive to a confirmation signal indicative of a confirmationby the human operator that said processing unit has correctly recognizedthe speech information to allow the locomotive to execute the command.12. A lead controller as defined in claim 11, wherein said processingunit is responsive to the confirmation signal indicative of aconfirmation by the human operator that said processing unit hascorrectly recognized the speech information to cause transmission of thecommand over the communication link.
 13. A lead controller as defined inclaim 12, wherein the confirmation signal is a signal derived frommanual actuation of a control on said lead controller.
 14. A leadcontroller as defined in claim 11, wherein the confirmation signalincludes speech information.
 15. A lead controller as defined in claim14, wherein said processing unit is operative to perform speechrecognition on the confirmation signal.
 16. A lead controller as definedin claim 11, wherein said processing unit prevents execution of thecommand by the locomotive unless the confirmation signal has beenreceived within a predetermined time period.
 17. A lead controller asdefined in claim 11, wherein said processing unit negates the speechrecognition results when no confirmation signal has been received withina predetermined time period.
 18. A lead controller as defined in claim1, wherein said speech recognition engine is speaker dependent.
 19. Alead controller as defined in claim 1, including a speaker verificationunit.
 20. A read controller as defined in claim 1, wherein said speechinput is a distance command.
 21. A lead controller as defined in claim1, wherein said speech input is a target location command.
 22. A leadcontroller as defined in claim 1, further comprising an input interfacefor receiving: a) a command for execution by the train; and b) aparameter of the train.
 23. A lead controller as defined in claim 1,wherein the locomotive is operative for riding on a track, said leadcontroller comprising an input interface for receiving a command forexecution by the locomotive and a parameter of the track.
 24. A remotecontrol system for a locomotive, comprising: a) a lead controller remotefrom the locomotive; b) a follower controller for mounting on thelocomotive; c) said lead controller operative for wirelesslytransmitting information to said follower controller; d) an input onsaid lead controller for receiving a signal containing speechinformation; a) a processing unit receiving the speech information andperforming speech recognition to generate speech recognition results andusing the speech recognition results to produce a command for executionby the locomotive, wherein said processing unit resides in said leadcontroller.
 25. A remote control system as defined in claim 24, whereinsaid follower controller is responsive to the command for generatinglocal signals for application to the locomotive to cause the locomotiveto execute the command.
 26. A remote control system as defined in claim25, including a microphone at said lead controller.
 27. A remote controlsystem as defined in claim 25, wherein the signal containing speechinformation is derived from a spoken utterance, said processing unit hasa speech recognition engine.
 28. A remote control system as defined inclaim 27, wherein said processing unit includes a speech recognitiondictionary including a plurality of vocabulary items, said speechrecognition engine being operative to identify amongst the plurality ofvocabulary items at least one vocabulary item that is a match to thespoken utterance.
 29. A remote control system as defined in claim 27,wherein said processing unit is operative to communicate to a humanoperator information allowing the operator to ascertain if theprocessing unit has correctly recognized the speech information.
 30. Aremote control system as defined in claim 29, wherein the informationallows the human operator to ascertain the speech recognition resultsgenerated by said processing unit.
 31. A remote control system asdefined in claim 30, wherein the information allows the human operatorto ascertain the at least one vocabulary item identified by said speechrecognition engine as being a match to the spoken utterance.
 32. Aremote control system as defined in claim 30, wherein said processingunit communicates the information to the human operator audibly.
 33. Aremote control system as defined in claim 32, wherein said processingunit communicates the information to the human operator visually.
 34. Aremote control system as defined in claim 32, wherein the information isconveyed to the human operator by using synthetic speech.
 35. A remotecontrol system as defined in claim 29, wherein said processing: unit isresponsive to a confirmation signal indicative of a confirmation by thehuman operator that said processing unit has correctly recognized thespeech information to allow the locomotive to execute the command.
 36. Aremote control system as defined in claim 35, wherein the confirmationsignal includes speech information.
 37. A remote control system asdefined in claim 36, wherein said processing unit is operative toperform speech recognition on the confirmation signal.
 38. A remotecontrol system as defined in claim 35, wherein the confirmation signalis a signal derived from manual actuation of a control on said leadcontroller.
 39. A remote control system as defined in claim 35, whereinsaid processing unit prevents execution of the command by the locomotiveunless the confirmation signal has been received within a predeterminedtime period.
 40. A lead controller as defined in claim 35, wherein saidprocessing unit negates the speech recognition results when noconfirmation signal has been received within a predetermined timeperiod.
 41. A remote control system as defined in claim 24, wherein saidspeech recognition engine is speaker dependent.
 42. A remote controlsystem as defined in claim 24, including a speaker verification unit.43. A remote control system as defined in claim 24, wherein said speechinformation includes a distance command.
 44. A remote control system asdefined in claim 24, wherein said speech information includes a targetlocation command.
 45. A remote control system as defined in claim 24,wherein said lead controller further comprises and input interface forreceiving: a) a command for execution by the train; and b) a parameterof the train.
 46. A remote control system as defined in claim 24,wherein the locomotive is operative for riding on a track, said leadcontroller further comprising an input interface for receiving a commandfor execution by the locomotive and a parameter of the track.